The invention relates to nozzles for solid fuel rockets, especially for single mission rockets. The nozzles of solid fuel nozzles must satisfy the following demands:
to obtain optimum efficiency it is necessary to operate at the highest temperature possible, within the limits of the material properties, PA0 the temperature gradient is extremely steep because the maximum temperature is reached only milliseconds after ignition, PA0 mechanically they must be able to withstand the pressure forces inside the rocket and the thrust generated by the gas jet, PA0 uncombusted metal of the fuel causes high energy knocks on the surface, PA0 suspended solid particles in the gas mixture cause mechanical abrasion in the throat region, PA0 free oxygen or other aggressive gases cause chemical corrosion.
Currently, rocket nozzles are made from graphite, tungsten, or metal carbides. It is known that silicon carbide shows extremely low rates of ablation. On the other hand, silicon carbide has severe tendency to suffer from cracks caused by the thermal expansion of the inner layer realtive to the outer layers. This excludes silicon carbide for rocket applications.